package layer // import "github.com/docker/docker/layer" import ( "fmt" "math/rand" "os" "path/filepath" "strings" "syscall" "testing" "github.com/docker/docker/pkg/stringid" "github.com/opencontainers/go-digest" ) func randomLayerID(seed int64) ChainID { r := rand.New(rand.NewSource(seed)) return ChainID(digest.FromBytes([]byte(fmt.Sprintf("%d", r.Int63())))) } func newFileMetadataStore(t *testing.T) (*fileMetadataStore, string, func()) { td, err := os.MkdirTemp("", "layers-") if err != nil { t.Fatal(err) } fms, err := newFSMetadataStore(td) if err != nil { t.Fatal(err) } return fms, td, func() { if err := os.RemoveAll(td); err != nil { t.Logf("Failed to cleanup %q: %s", td, err) } } } func assertNotDirectoryError(t *testing.T, err error) { perr, ok := err.(*os.PathError) if !ok { t.Fatalf("Unexpected error %#v, expected path error", err) } if perr.Err != syscall.ENOTDIR { t.Fatalf("Unexpected error %s, expected %s", perr.Err, syscall.ENOTDIR) } } func TestCommitFailure(t *testing.T) { fms, td, cleanup := newFileMetadataStore(t) defer cleanup() if err := os.WriteFile(filepath.Join(td, "sha256"), []byte("was here first!"), 0o644); err != nil { t.Fatal(err) } tx, err := fms.StartTransaction() if err != nil { t.Fatal(err) } if err := tx.SetSize(0); err != nil { t.Fatal(err) } err = tx.Commit(randomLayerID(5)) if err == nil { t.Fatalf("Expected error committing with invalid layer parent directory") } assertNotDirectoryError(t, err) } func TestStartTransactionFailure(t *testing.T) { fms, td, cleanup := newFileMetadataStore(t) defer cleanup() if err := os.WriteFile(filepath.Join(td, "tmp"), []byte("was here first!"), 0o644); err != nil { t.Fatal(err) } _, err := fms.StartTransaction() if err == nil { t.Fatalf("Expected error starting transaction with invalid layer parent directory") } assertNotDirectoryError(t, err) if err := os.Remove(filepath.Join(td, "tmp")); err != nil { t.Fatal(err) } tx, err := fms.StartTransaction() if err != nil { t.Fatal(err) } if expected := filepath.Join(td, "tmp"); strings.HasPrefix(expected, tx.String()) { t.Fatalf("Unexpected transaction string %q, expected prefix %q", tx.String(), expected) } if err := tx.Cancel(); err != nil { t.Fatal(err) } } func TestGetOrphan(t *testing.T) { fms, td, cleanup := newFileMetadataStore(t) defer cleanup() layerRoot := filepath.Join(td, "sha256") if err := os.MkdirAll(layerRoot, 0o755); err != nil { t.Fatal(err) } tx, err := fms.StartTransaction() if err != nil { t.Fatal(err) } layerid := randomLayerID(5) err = tx.Commit(layerid) if err != nil { t.Fatal(err) } layerPath := fms.getLayerDirectory(layerid) if err := os.WriteFile(filepath.Join(layerPath, "cache-id"), []byte(stringid.GenerateRandomID()), 0o644); err != nil { t.Fatal(err) } orphanLayers, err := fms.getOrphan() if err != nil { t.Fatal(err) } if len(orphanLayers) != 0 { t.Fatalf("Expected to have zero orphan layers") } layeridSplit := strings.Split(layerid.String(), ":") newPath := filepath.Join(layerRoot, fmt.Sprintf("%s-%s-removing", layeridSplit[1], stringid.GenerateRandomID())) err = os.Rename(layerPath, newPath) if err != nil { t.Fatal(err) } orphanLayers, err = fms.getOrphan() if err != nil { t.Fatal(err) } if len(orphanLayers) != 1 { t.Fatalf("Expected to have one orphan layer") } }